Tuesday's primaries: What to watch for

/ Source: NBC News and msnbc.com

It’s Tuesday, and in this mid-term election year that means it’s almost certain that voting is going on somewhere in the United States.

The primary season is well underway, and this week brings contested races in Mississippi, New Mexico, and Alabama to watch.  Here are the story lines to keep an eye on as results roll in, courtesy of the NBC News Political Unit.

Could Alabama take a step toward electing its first black governor?
In the Democratic primary, Rep. Artur Davis will face off Tuesday against Agriculture Commissioner Ron Sparks. If he bests Sparks in the primary, Davis will make history as the first black nominee of either party for governor of the once-segregated Alabama. Either Democrat would likely face an uphill battle this fall against the Republicans.

Davis hopes that his vote against the Democratic-backed health care overhaul bill earlier this year will help him in this conservative state. But that vote cost him the endorsement of many of the state’s prominent civil rights organizations.

Will Griffith go the way of Specter?
When Rep. Parker Griffith, D-Ala. switched from the Democratic to the Republican party last year, he stepped into an already-tough primary between county commissioner Mo Brooks and former Navy pilot Les Phillips. Griffith’s opponents have made the freshman congressman’s party-switch the central issue of the race.

(Another party-switcher, Sen. Arlen Specter of Pennsylvania, was defeated in his primary contest on May 18.)

This district has voted for a Republican in every presidential election since 1980, but it has never sent a Republican to Congress. The winner needs 50 percent of the primary vote to avoid a runoff election; with three candidates, it seems likely that none of the candidates will meet that threshold.

How will a GOP establishment pick fare in Mississippi?
Mississippi’s 1st district is held by Democrat Travis Childers, but it's a seat Republicans are targeting — and should have a good chance at flipping — in the November general election. But there's a tough three-way primary between state Sen. Alan Nunnelee, small-town mayor Henry Ross, and former Fox News contributor Angela McGlowan. (Nunnelee is the favored pick of national GOP establishment leaders.)

Like Griffith’s Alabama race, this one is likely headed to a runoff, and Democrats think they have a good shot of holding the seat in the fall if Ross wins. If they're right, the November contest could end up as another example of how Republican infighting has placed put the GOP’s most likely House seat pickups in jeopardy.

How much of a boost are ads worth in Alabama?
The Republican primary in Alabama governor's race has provided some of the most provocative ads of 2010 so far.

Front-runner Bradley Byrne was targeted by a conservative interest group for failing to take the Bible’s teachings on evolution literally enough.

Another ad from businessman Tim James, which urges that the state’s driver's license exam should only be administered in English, has received almost a million YouTube hits. "This is Alabama," he says in the campaign ad. "We speak English. If you want to live here, learn it."

James has seen an uptick in his poll numbers since the airing of those ads. He is likely headed for a second-place finish and a runoff with Byrne.

A third candidate in the race is Roy Moore, a former chief state Supreme Court justice, who was ousted from the bench for refusing to remove a 5,300-pound display of the Ten Commandments from the state courthouse.

Will Republicans position themselves to flip the New Mexico governor’s mansion?
Republicans are hoping that Susana Martinez, a county prosecutor, survives the bitter New Mexico gubernatorial primary against former state party chairman Allen Weh.

Republicans believe that Martinez, who also has Sarah Palin's backing, has the best shot at beating the Democratic candidate, Lt. Gov. Diane Denish, who is favored in the fall.