The buzz is getting louder that House Speaker Paul Ryan could be tapped as the GOP presidential nominee in the event of a brokered Republican convention this summer.In a column for The Hill, former Rep. Bill Owens, a New York Democrat, writes the once unlikely scenario seems a distinct possibility with establishment Republicans having "grave concerns" about both front-runner Donald Trump and second-place Ted Cruz.Owens notes the reluctance of GOP fundraisers to support this year's candidates with the sort of money they threw at Mitt Romney in 2012 means they believe Donald Trump, Ted Cruz or John Kasich cannot win the general election.Meanwhile, Ryan, a Wisconsin Republican, "consistently talks about setting a tone that is inclusive and policy-focused with an agenda that is inspirational, inclusive and optimistic. Let us not forget he acquired national campaign experience as Romney's running mate …" writes Owens, a strategic adviser at the global law firm Dentons."It is also likely that if the Republican presidential field continues to implode, making incredibly demeaning and racially provocative comments, it is clear that a call for a brokered convention may rise to a crescendo and a ground swell of support for Ryan could emerge."Ryan has said he has no interest in running for president, but then again he also said he had no interest in replacing John Boehner as House Speaker.