Are political conventions necessary? Texas Democrats are in Houston for their state convention. Texas Republicans are in Fort Worth for the same thing. The Libertarians are meeting this weekend near DFW Airport, and the Green Party is having its convention outside San Antonio. It’s actually easier to make the convention case for the Libertarians and the Greens, who use their gatherings to put people on the ballot, because they don’t hold primary elections. The two major parties, on the other hand, held their primaries on May 29 and will sort out the remaining 37 contests in runoffs on July 31. The conventioneers don’t have anything to do with that, except when they vote back home. They are at their conventions to elect the officers of their party and the executive committee members who meet periodically to handle party business, as well as to pick the delegates and others who will get passes and floor and voting rights at the national conventions this summer. Whether those conventions are still necessary is another open question, but this is about the state contests. How many people need to be at these gatherings? Is this a scam invented by the state’s convention and visitors bureaus and the rest of the travel industry? Is it meant just to get some publicity for the parties and candidates? To get the party faithful enthused for the remaining five months of the political season? To make money? And, as a selfish and personal side note, how is it that both of the political parties landed their conventions in the only two places in Texas with Major League Baseball teams, on a weekend when the Astros and the Rangers are, respectively, in Chicago and San Francisco? Do the teams know something we don’t? Do the planners want everyone to concentrate and avoid sports and other amusements? State conventions don’t usually make news — other than the perfunctory official business stories — unless candidates say amazing things or partisans get into arguments. Texas Democrats have historically made news with their intramural fights, where two caucuses take opposite positions and put everyone else in the party on edge, or when two or more groups contend to represent the same part of the party. Texas Republicans almost always make news with their platform, which is full of specific programs and planks that spook candidates and other Republicans alike. The Democrats have a long list of weird caucuses. The Republicans fly their colors in their platform. These are conventions, after all, for the most Republican Republicans and the most Democratic Democrats. They are fervent, like ham radio operators or model rocketeers, quilters or comic book collectors. The conventions rally the faithful. Like those various and numerous rabid hobbyists, political people find comfort with members of their own herd. It’s not appropriate in most other settings to put on that vest with 57 different campaign buttons, that bowler with the red, white and blue sequins, or the old Ross Perot T-shirt. And the conventions do give the partisans a chance to see many of the people on their ticket, like them or not. But not the big dogs: Mitt Romney didn’t schedule a visit to the Republican convention in Fort Worth. President Obama wasn’t planning a stop in Houston. Unless they’re looking for money, presidential candidates from both parties ignore us, assuming that the state will hand its electoral votes to whatever Republican gets the nomination. That’s been a safe bet for more than 30 years. These can be risky places even for the locals. On Thursday, the crowd at the Republican convention roared with boos when Gov. Rick Perry reasserted his support for Lt. Gov. David Dewhurst, now a United States Senate candidate. Tough crowd. Soon, they’ll be gone. The Fort Worth Convention Center will get ready for real estate asset managers and then for a gathering of Jehovah’s Witnesses. Houston’s George R. Brown Convention Center will get the State Bar and then a gun and knife show. The delegates, energized and/or exhausted, will pack up the vests and funny hats and get to work on elections, safe in the knowledge that they are a part of something bigger than themselves.