How Texas’ fuzzy math, and Bush, help Obama

That's unwelcome news for Clinton, who has won strong support from Hispanic voters in other states.

She faces other Texas obstacles in eroding Obama's national delegate advantage.

Within each state Senate district, delegates are awarded in rough proportion to the popular vote. That presents a daunting challenge to any candidate hoping to sweep most or all the delegates and run up a big lead.

Of the 31 state Senate districts, 15 have four delegates apiece. Under party rules, unless the winner gains nearly 63 percent of the vote, Clinton and Obama will each walk away with two delegates, and neither will gain ground.

Another nine districts, scattered around the state, have three delegates apiece. The odds overwhelmingly favor a 2-to-1 split, since the winner would have to gain more than 83 percent of the vote to score a 3-0 sweep.

One district, in West Texas, has two delegates, and the winner there would need 75 percent of the vote to win both.

Two districts have five delegates apiece. The likeliest outcome is a 3-2 delegate split, since the winner will need 70 percent of the vote to get a 4-1 victory.

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Two more districts each have six delegates. But the winner needs 75 percent of the vote for the winner to gain more than a 4-2 split.

A district in Houston offers seven delegates, and the odds favor a 4-3 split.

Austin district has most delegates
The state Senate district with the most delegates, eight, is centered on Austin. The winner there needs slightly over 56 percent to gain even five of the eight, and nearly 69 percent of the vote to gain a 6-2 split.

Most states that hold primaries award a delegate bonus to the winner of the primary vote in rough proportion to the popular vote.

But not Texas.

In effect, the caucuses replace that system, adding yet another level of complexity and competition.

Only primary voters are eligible to participate in the caucuses, one of which will be held in each of the state's 8,247 precincts.

Each caucus will elect one delegate to attend county conventions for every 15 votes the precinct cast for Bell in 2006, when he won the black vote easily, but trailed among Hispanics.

That will eventually lead to a state convention on June 6 where Obama and Clinton divide the 67 national delegates.

Picking the president: The candidates Click to visit that candidate's MSNBC page or click the XML symbol for an RSS feed. John McCain                Barack Obama

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