经过数月的集会、演讲和辩论后，美国总统选举的初选阶段于星期一正式开始，中西部爱奥华州的选民们将在党团会议地点投票。
在爱奥华州率先举行至关重要的2016年初选投票之前，该州民调显示，共和党和民主党的选情都十分胶着。
在共和党方面，房地产大亨川普继续以微弱优势领先于德克萨斯州联邦参议员克鲁兹。在爱奥华州初选即将开始之际，克鲁兹看来有过几次失误。
在民主党方面，前国务卿希拉里·克林顿和佛蒙特州联邦参议员桑德斯几乎并驾齐驱。桑德斯自称是民主社会主义者。
两党总统参选人星期日在爱奥华州做了最后冲刺，他们在爱奥华州各地发表演讲，加紧抨击对手，并在最后一刻争取重要选民组织的支持。
After months of rallies, speeches and debates, the U.S. primary election campaign is set to formally get under way Monday, when Iowa residents cast their presidential preference at caucus sites across the Midwestern state.
Ahead of the crucial, first-in-the-nation 2016 vote, opinion polls in Iowa revealed a tantalizingly close race for both the Republican and Democratic Party nominations.
On the Republican side, real estate developer Donald Trump maintains a slight lead over Texas Senator Ted Cruz, who appears to have made several missteps in the lead-up to the Iowa caucuses.
For the Democrats, the race seems to be a virtual tie between former secretary of state Hillary Clinton and Vermont Senator Bernie Sanders, the self-declared democratic socialist.
Candidates in both parties made a final sprint through Iowa Sunday, holding events in every corner of the state, stepping up attacks on rivals and making last-minute appeals to key voter groups.