Democrats have not held a U.S. Senate seat in Texas since 1993, but the party has attracted five hopefuls.One candidate hoping to unseat Sen. John Cornyn is Dallas dentist David Alameel, a Lebanese-born immigrant whose business acumen and professional success have earned him a small fortune.This is not Alameel’s first rodeo. He ran an unsuccessful bid for Congressional District 33 in 2012, finishing fourth among 11 Democratic primary candidates. The seat currently is held by Mark Veasey.Critics from within the party question his loyalty to Democratic principles and point to sizable campaign contributions to Republicans in past election cycles, including a donation to Cornyn. In response to these criticisms, Alameel has demanded a “refund” from the sitting senator and expressed disappointment in Republicans’ “lack of compassion for the common man.” He is certainly not the first Texan to have a political conversion experience (think: Sen. Phil Gramm). This shouldn’t discount him as a candidate.In addition to Alameel, the Democratic primary candidates are businessman Michael Fjetland; physician Harry Kim; political activist Kesha Rogers; and attorney Maxey Scherr.Fjetland’s extensive experience abroad makes him a self-described “student of the world,” which he sees as important in avoiding the mistakes of European democracies. He has also run for office before — three times as a Republican primary challenger to former Rep. Tom Delay — each time with minimal success at garnering widespread support.Kim told his local paper that Cornyn is relatively unknown and has wasted his position in the U.S. Senate. Beyond his calls to fight inequality, Kim’s platform appears to be relatively unknown as well.The unconventional candidacy of Rogers is somewhat puzzling. Her thorough responses to questions from the Star-Telegram Editorial Board focus on a platform to restore the Roosevelt-era Glass-Steagall banking regulations and to impeach President Obama (she advocated the same course for his predecessor, as well). It seems odd for her campaign to hinge on the impeachment of a Democratic president who, in spite of a recent dip the polls, remains popular among the party faithful.A single mom with a populist message, Scherr has the ability to appeal to a diverse Democratic audience. She supports most issues that matter to party members, including marriage equality, raising the minimum wage and increasing support for education and training. Scherr has attacked Alameel for his mixed messages on abortion rights. But she is unlikely to outraise his built-in war chest, leaving her at an extreme disadvantage.The Democratic field is disappointingly weak. No candidate appears to have the right combination of infrastructure, funding, platform and message.In order to pose a serious threat to a well-financed incumbent, successful challengers typically need three things: money, infrastructure and support from other popular candidates and elected officials.Alameel lacks a strong message, but his personal fortune ensures a well-financed campaign, and he has garnered endorsements from the party’s biggest players, including newly anointed Democratic gubernatorial candidate Wendy Davis.He is likely the party’s best chance to defeat a well-funded Republican in the general election.The Star-Telegram Editorial Board recommends David Alameel in the Democratic primary for U.S. Senate.