From a deal with Iran to an uptick in the employment rolls, a lot can happen to shift the political conversation between now and November.

Immigration reform, for example, was supposed to help Democrats in the midterm elections. Clashes on the border between angry Texans and buses carrying immigrant children fleeing gang violence and sex trafficking highlighted the GOP’s opposition, and Democrats thought maybe this was the game changer they needed.

But the consensus among Republicans and Democrats interviewed for this article is that President Obama squandered his party’s advantage on immigration when he was blindsided by the sudden influx of children from Central America, and then didn’t do much to deal with the crisis until it became a big national story.

Frank Luntz, who helped steer the GOP to its House majority in 1994, says what’s happening in Texas has captivated public attention and could negatively impact the Democrats more than anything else this year, including health care. “No one expected us to lose control of the border,” he says, and when something unexpected happens, that’s the definition of a game changer.

“You want another game changer,” he added, “Rick Perry went from no contender to serious contender in 24 hours. He has been completely rehabilitated.”

Democrats counting on an energized Hispanic vote in November are looking to Obama to retrieve the situation with whatever executive orders he can come up with. But Brookings senior fellow William Galston says almost any response is going to involve some steps pro-immigration advocates are not going to like. “While Hispanics are angry and disaffected with the Republicans, they’re bitterly disappointed with the Democrats.”

Yet some things could happen between now and November that might alter the public mood, says Galston. An historic agreement to derail Iran’s nuclear program would be a diplomatic achievement on the scale of Camp David, and would disrupt the current narrative that Obama can’t do anything right.

Even more important to voters could be an improving economy, especially if unemployment drops below 6 percent, which it is likely to do. Alternatively, a sudden oil shock stemming from the turbulent events in the Middle East is also possible, and would counter any good economic news.

Midterm races generally crystallize in mid-summer, and the House is expected to stay firmly in GOP hands. Political handicapper Charlie Cook points out that 96 percent of Democrats are in seats Obama won, and 93 percent of Republicans are in districts Mitt Romney won, leaving very few competitive swing districts.

The Senate is the big prize, and Republicans can gain the majority just winning seats in red states that Romney carried. “What happens in the Senate is less about the environment than where the races are,” says Cook. Democrats, he says, are facing “an ugly map.”

Obamacare is still a big driver, but it’s not the unalloyed gift Republicans had banked on. A survey last month for NBC and the Wall Street Journal conducted by Republican pollster Bill McInturff and Democratic pollster Peter Hart found the biggest liability for Democrats is a lack of time to alter the negative impression about the health care law, which is taking hold with millions of happy enrollees. For Republicans, the biggest liability is that voters aren’t buying the GOP’s “repeal and replace” message, preferring “fix and keep” instead.

The Supreme Court’s Hobby Lobby decision giving closely-held family corporations veto power over contraceptive coverage jump-starts the Democrats’ “war on women” theme and could help turn out single women who, when they vote, support Democrats. House Speaker John Boehner’s lawsuit against the president, a proxy for impeachment, gets Democratic activists revved up, but most analysts dismiss it as a political stunt that’s going nowhere.

“Just noise,” says Luntz, who despite his bullishness on how the border crisis is helping the GOP, says he “must be the only person right of center who isn’t convinced Republicans will win the Senate.” Asked to explain, he says opposition to Obama and Senate leader Harry Reid is “not enough. Candidates need to be heard. They have to have a reason to be elected.”

GOP consultant Kevin Madden thinks he has found the perfect issue for Republicans to champion: increased investment in early childhood programs. A bipartisan poll being released Thursday by the First Five Years Fund shows sizeable majorities of Democrats, Independents and Republicans favoring more government programs for preschoolers, with evidence that every dollar spent saves seven dollars in benefits down the road.

The Fund’s executive director, Kris Perry, thinks it’s the perfect issue for the GOP’s emerging generation of intellectuals, dubbed “Reformicons,” who are searching for ideas to ease their party’s hard-line image. Having failed to win the Senate in the last two election cycles because of candidates that were preposterous in their views and rhetoric, Republicans are much more savvy this time around.

For one thing, there won’t be any town meetings in August for candidates to attract unwanted attention. “Members have found ways to avoid town hall meetings with teleconferences or invitation-only meetings,” says Jack Pitney, professor of politics at Claremont McKenna College.

Even with the deck stacked against them, Democrats can take heart in two things, says Pitney. “Republicans are perfectly capable of botching races, and with the Senate, Democrats lose in 2014, they gain it in 2016.” In two years, it will be the Republicans’ turn to face an ugly map, and the search for game changers will begin anew.