PHILADELPHIA _ The Republican convention has generated a modest increase so far in Donald Trump's poll standing, moving the New York businessman back into a lead over Hillary Clinton.
Through Sunday, the University of Southern California Dornsife/Los Angeles Times "Daybreak" tracking poll of the race shows Trump gaining about 3 percentage points in the aftermath of the convention. That would be roughly in line with the convention bounces enjoyed by Democratic and Republican nominees in the past three election cycles.
As of Sunday, the poll, which is updated daily, showed Trump leading Clinton 45 percent to 41 percent. The lead is within the poll's margin of error of 3 percentage points in either direction, meaning that the apparent lead could be the result of chance.
Trump had led Clinton by a similar margin a week before the GOP convention started, after the sharp criticism the former secretary of state received from FBI Director James Comey over her handling of classified information in her emails while in that office. But his support declined in the days immediately before the convention, and the two were tied in the poll for much of the past week.
While the convention appears to have shifted some voters back to Trump, it also seems to have increased the intention to vote among Clinton's backers.
A similar increase for Trump has showed up in some other surveys. A poll by Morning Consult, a polling and media firm, showed him taking a 44 percent to 40 percent lead, the first time he has had the advantage in that poll. Trump got a slightly larger increase in the latest CNN/ORC survey _ a six-point bump, which moved him from trailing Clinton in that poll to leading, 48 percent to 45 percent. When tested in a four-way matchup that included Gary Johnson, the Libertarian candidate and Jill Stein of the Green Party, Trump led 44 percent to 39 percent, with Johnson getting 9 percent and Stein 3 percent, the CNN/ORC poll found.
Both parties usually experience an increase in support after their conventions, which typically are among the few events in a presidential race that actually move large numbers of voters.
The increase usually stems from two things: Conventions tend to strengthen partisan feelings, so a party's voters typically coalesce around the nominee during or just after the gathering. The convention is also the one time during a campaign in which one party gets disproportionate attention to its message. That typically sways some voters who don't have strong partisan feelings.
In some cases, candidates can get a large and lasting increase from the convention, most notably 1992, when then-Gov. Bill Clinton gained as much as 14 points in some surveys taken just after the Democratic convention.
More recently, however, the trend has been toward smaller post-convention bounces, probably because the country has fewer swing voters.
The Daybreak tracking poll is part of the Understanding America Study conducted by USC's Dornsife Center for Economic and Social Research. The election survey is being done in partnership with the Times and USC's Jesse M. Unruh Institute of Politics.
