washington senior democrats say monday chance win control u.s. house representatives hurt fbi surprise announcement last month hillary clinton email practice figure federal investigation voters go poll tuesday choose democrat clinton republican donald trump president also fill 34 u.s. senate seat 100-chamber body 435 house seat house senate currently control republicans fbi director jam comey letter congress late october agency would examine newly find email might pertain clinton use private server secretary state tremendous adverse impact stand independents say representative jam clyburn member house democratic leadership refer independent voters house democratic leader nancy pelosi call comey action line say result spike small campaign donations add would good place without letter manner it clyburn pelosi remark see reuters deliver phone call house democratic leaders rank-and-file members continue republican control congress could stymie legislative agenda put forth clinton win presidency trump win along republican congress could spell doom democratic president barack obama landmark healthcare law know obamacare target sustain attack republican lawmakers voters hand power democrats either chamber 2017 likely bring moderate bend bill lawmakers send new president sign law senior democratic aide say october controversy consume u.s. political campaign week could reduce least 10 number house seat democrats may able capture republicans election day comey inform congress sunday stand july decision criminal charge warrant democratic presidential candidate email investigation come two days national elections comey late decision may come late democrats hop big win tuesday help regain control house first time since 2010 senate first time since 2014 terribly damage us aide say add clinton support battleground state could depress turn would hurt party house candidates mind aide say democrats could end gain 12 16 house seat tuesday instead 30 need win back chamber representative tom cole senior house republican say telephone interview find mystify comey interject election three different occasion ways probably inappropriate cole refer initial announcement july clinton would prosecute late october letter congress fbi agents review issue sunday information agency would change july find sunday good news clinton oklahoma lawmaker say think certainly take little steam republicans win control senate outright democrats would score net gain five seat republicans currently hold 54 senate seat 44 democratic seat two independents align democrats much autumn campaign political analysts project democrats would pick anywhere four seven senate seat outcome presidential race expect major impact outcome congressional campaign recent decades party win white house usually fare good congressional race 2016 campaign season senate race center stage democrats field strong challengers republican incumbents among missouri secretary state jason kander give republican senator roy blunt unexpectedly stiff challenge former environmental official katie mcginty could unseat republican senator pat toomey pennsylvania john mccain vietnam war hero 2008 republican presidential nominee serve senate 30 years appear head re-election race unusually competitive possible 50-50 tie follow tuesday elections would mean next vice president would cast tie-breaking vote determine party control senate senate swear jan. whether hold republicans democrats face weighty decision early vote u.s. supreme court justice replace conservative justice antonin scalia die last february since time senate republicans refuse consider obama nomination federal judge merrick garland argue next president pick nominee senate review issue confront congress next year include illegal immigration border security need raise u.s. borrow authority something conservative republicans oppose without substantial budget cut possible approval free-trade deal pacific rim countries europe negotiations latter conclude successfully democrats see fbi controversy hurt chance u.s. congress race