Problem with Pulling Event Entries The following code is throwing an error for me.

{% set eventEntries = craft.entries.find({
    section: 'events',
    event_startDateTime: '&lt;= {{ now }}',
    limit: '4'
}) %}

{% for entry in eventEntries %}


Fatal error: Call to a member function getTimestamp() on a non-object

What I'm trying to do is pull 4 events where a date field (event_startDateTime) is before the current time.  My suspicion is that the {{ now }} variable isn't parsing inside the single quotes, but I'm not entirely sure.  Can anyone correct my code?
In Twig, you'll never need to double up on your curly brackets.  I.E.

{{ {{ }} }}


or 

{% {{ }} %}


Change this (which is already inside of {% %}:

event_startDateTime: '&lt;= {{ now }}',


To use string concatenation like this:

event_startDateTime: '&lt;= ' ~ now,


And you should be set.