The ng-model
is not a standard attribute, so Watir-Webdriver does not directly support the attribute as a locator.
One option is to use a css-selector:
browser.element(:css=> 'input[ng-model="pollObj.poll_question.start_time"]').when_present.click
Or you could use xpath:
browser.input(:xpath => './/input[@ng-model="pollObj.poll_question.start_time"]').when_present.click