Despite lowering expectations after a string of losses, Democratic hopeful Hillary Clinton still holds double-digit leads over Barack Obama in Ohio and Pennsylvania, both crucial states in upcoming primaries:

– According to a Quinnipiac University poll released Thursday, Clinton leads 55-34 percent among likely Democratic primary voters in Ohio.
– Among Ohio Democrats, women back Clinton, 56-30 percent for Obama, while men back Clinton 52-42 percent, the poll found.
– White Democrats favor Clinton 64-28 percent, while Obama leads 64-17 percent among black voters, according to the survey.
– The survey also found a formidable lead for Clinton among likely Democratic primary voters in Pennsylvania - 52-36 percent.

The Quinnipiac University poll was taken February 6-12, after Obama and Clinton virtually knotted 22 Super Tuesday contests. However, his eight straight wins since may not be fully reflected here.

Ohio, Rhode Island, Texas and Vermont hold nominating contests March 4, while Pennsylvania voters will go to the polls April 22.

Wisconsin - where Obama gave a stirring speech after winning the Potomac primaries February 12 - and Hawaii vote next Tuesday.

There is no denying that Ohio, Pennsylvania and Texas shape up better for Hillary Clinton than recent states were Obama has coasted. But how much better - especially as Obama’s legitimacy grows by the day - is unclear.

That said, Texas accounts for 228 delegates, and if Barack Obama can pull off an upset, it would tilt the nomination heavily in his favor.

IVR Polls, which surveys voters via automated voice responses, has been checking the pulse of Texas voters for nearly a year, and had Obama at 10 points behind Clinton as of January 31, down 48-38 percent.

Illustrating just how well Barack Obama connects with voters once he gets some exposure, Clinton held a 51-17 percent lead as recently as December.

Also working in Obama’s favor are the complex Texas primary rules.

The Houston Chronicle points out that while Clinton seeks traction in the Lone Star State, it might be slippery footing, as not all of Texas’ congressional districts get an even number of delegates.

Some districts get more delegates if they had higher turnouts in the 2004 presidential race and the 2006 gubernatorial election.

The Chronicle says at least two predominantly African-American districts in suburban Dallas had higher turnout than, for example, two heavily Hispanic districts in Brownsville. So that’s something to think about.

Barack Obama has obtained 80 percent of the African-American vote so far, while Clinton is getting roughly 60 percent of Hispanic votes.