Political scientist Sam Best is analyzing Republican primary results for CBS News. When the polls close, he has to be ready to explain which candidates did well and why, and who is in trouble.

With the Republican frontrunner changing almost weekly, the race to the nomination is constantly in the news. “This year the momentum hasn’t even carried to the next contest,” says Best, an associate professor of political science in the College of Liberal Arts and Sciences.

Just after the first Florida debate, he answered these questions about the fast-changing race to the nomination.

What resources are available to you as a basis for your analyses?

My job is to interpret the outcome of a given contest, explaining why some candidates did well and others did poorly. I rely primarily on the entrance/exit polls, but also draw on pre-election surveys, speech and debate transcripts, financial disclosures, and past race results.

Are you on the ground with the candidates in the primary states?

I work out of CBS News in New York, analyzing exit polls and vote returns as they come into the network.

How quickly do you have to file your analysis after the polls close?

My stories have to be submitted within a few hours of the polls closing. The tight deadlines require to you be up to speed on all facets of a race, because on election night there simply is not enough time to do background research.

What surprises you about the Republican primary contests so far?

The volatility. This is one of the most volatile campaigns to date. In the last six months of 2011, four different candidates topped the national polls. Six different candidates topped the pre-election polls in the first competitive contest – the Iowa Caucuses. And after the first three races, we’ve had three different winners. Typically, one candidate gains the momentum after Iowa or New Hampshire and coasts to victory. This year the momentum hasn’t even carried to the next contest.

How can Mitt Romney gain the support of conservatives and low-income voters?

This will be difficult. Conservatives are wary of his time as Massachusetts governor, when he introduced a health care plan similar to the one adopted by President Obama, and he supported gay rights, gun control, stem cell research, and reproductive rights for women. Although he has changed his position on these issues, many conservatives remain skeptical.

You’ve attributed Newt Gingrich’s quick turnaround in South Carolina to debate success. Can that strategy carry him into the nomination?

Debate performances won’t be enough, because of the timing and the nature of the upcoming contests. So far, we’ve had a contest each week, with a couple debates occurring in the days leading up to them. After Florida, the calendar changes dramatically, making money and organization far more important. The first week of February brings caucuses in four states – Nevada, Maine, Colorado, and Minnesota – where Romney’s organizational advantages will likely yield dividends. February concludes with primaries in Arizona and Michigan, locations that are more conducive to Romney. Arizona has a sizable number of Mormon voters, while Michigan is where Romney was born and raised and his father was a popular governor. Together, though, these contests account for only 8 percent of the delegates up for grabs. If Gingrich can soften expectations and remain at least competitive – both daunting tasks – then he can attempt to turn the tide on Super Tuesday in the first week in March, when roughly 25 percent of the delegates are at stake in a number of conservative states in the south.

If Rick Santorum doesn’t drop out, could Gingrich still get the nomination?

It will be difficult for Gingrich to win the nomination if Santorum remains in the race. They both appeal to the conservative wing of the Republican Party, attracting similar types of voters.

What role will the Tea Partiers play in the national election? You’ve mentioned that they won’t back Romney, if he’s the nominee. Would that be fatal to his election?

Support for the Tea Party movement has waned some since 2010. However, it still is capable of making an impact in Republican primary races in some areas of the country, as South Carolina proved. It is unlikely to play much of a role in the 2012 presidential race because most of its most fervent supporters were unlikely to have ever supported President Obama and/or Democratic nominees.

Do the concerns of primary voters reflect the concerns you expect to see from voters in the general election, or are they more exclusive to Republicans?

Voters in the Republican primaries have continually emphasized the economy and job growth. With unemployment likely to remain over 8 percent when the general election campaign unfolds, it should remain the key issue to voters of all stripes come Election Day.

Will you be an analyst in the fall campaign?

I will again work for CBS News during the fall campaign, analyzing exit polls and interpreting the outcome of the presidential election as well as Senate and House races.

Read more: Best’s analysis of Newt Gingrich’s chances.