Earlier this week there was much ado about the fact that Barack Obama had reached the 50% mark in the Gallup Tracking Poll. Just out was the latest update showing that that “lead” had been cut in half. Like the Rasmussen Poll released this morning two thirds of the data was collected BEFORE the Governor Palin speech on Wednesday. Historical trends would indicate that Obama’s bounce will be larger than McCains because his convention was first. Look for Monday’s results where it looks as if that Historical trend will be shattered. The full Gallup info follows:

Gallup Daily: Obama’s Lead Now at 4 Points Obama’s position about halfway between his recent highs and lows

PRINCETON, NJ — Gallup Poll Daily tracking from Tuesday through Thursday finds Barack Obama with a four-percentage-point lead over John McCain in the presidential preferences of registered voters, 48% to 44%. While the difference between today’s result and Thursday’s 49% to 42% lead for Obama is not statistically significant, some of the broader shifts seen over the past 10 days, spanning both party’s national conventions, have been meaningful. Support for Obama since just before the Democratic National Convention kicked off on Aug. 25 has ranged from 44% to 50%, while McCain’s support has ranged from 41% to 46%. Whereas the race was initially tied at 45%, Obama pulled into an eight-point lead at several points over the course of his convention. It now appears the Republican National Convention may be helping McCain to recoup some of his losses, though with Obama’s current four-point lead, the entire convention period to this point has still been a net plus for Obama. (To view the complete trend since March 7, 2008, click here.) While both conventions are now over, measurement of public reaction to them is not. Results, based on interviewing conducted Sept. 2-4, include just one day of interviewing conducted after Wednesday night’s widely viewed acceptance speech by McCain’s vice presidential running mate, Alaska Gov. Sarah Palin. Most interviewing Thursday night was conducted before McCain’s acceptance speech, so Gallup Poll Daily tracking results will start to reflect its impact in Saturday’s report. The full impact of the GOP convention on voter preferences will not be known until Monday’s report, the first in which all interviews will have been conducted following the convention’s conclusion. (Click here to see how the race currently breaks down by demographic subgroup.)